Analysis on Impact Strength of Secondary Battery Pack of Electric Torpedo

Safe and smooth discharge of secondary battery pack is a guarantee of normal navigation for an electric torpedo. The battery container is necessary to supply adequate space for battery monomer, and have certain impact strength as well to prevent internal short circuit of battery monomer caused by water-entry impact of torpedo’s air-dropped launching. In this study, water-entry impact test of air-dropped launching torpedo was conducted for the battery pack, and the results showed that the battery monomer was not damaged, but the battery container cover was seriously damaged. Then, the reason why the serious deformation of the container cover happens was analyzed by using impact finite element simulation, and the results indicated that the bending strength of the container cover was insufficient. Furthermore, the structure of the container cover was improved to enhance its bending strength, as a result, the battery pack in the improved container passed the subsequent impact test. This study may provide a reference for the impact resistance design of the battery pack.